Scandinavian gambit:
1.e4 d5 2.exd5 nf6
derp, obviously. OP plays BDG, so I doubt hes looking for a theoretical advantage
Other than the scandinavian gambit maybe:
1.c4 d5 2.cd5 c6, its called the vortex gambit or something like that.
1.d4 e5 2.dxe5 and now maybe d6..
From what I can think of those seem to run best with matching the openings you have so far.
I have vitalized My Chess fun by playing Blackmar-Diemer and Gibbins-Weidenhagen as white but I am looking for something similar as black. The Latvian has never worked for me but I am eager to test other UCO stuff.
Thank you in advance!